When combining with nonmetallic atoms, metallic atoms generally will Lose electrons and forms cations.

As the ionization energy of te metals are very low, so they can easily lose electrons and form positively charged ion called cations.

Speed = 108 km/hr
enter a tunnel,, means that the train covers a distance equal to its own length
so (108 x 5/18) = x/4 where x= length of train
hence x = 120 mtrs
to pass completely train has to travel a distance = (x + tunnel length) that is 1120 mtrs.
so (1120/t) = (108x5/18)
t = 37.33 sec

In Indian History, Dandi March or Salt Sathyagraha or The Salt March, also known as the Dandi Satyagraha, was an act of nonviolent civil disobedience in colonial India led by Mohandas Karamchand Gandhi to produce salt from the seawater. 

It is also called as 'White Flowing River'.

If a hub has three computers connected to it, one broadcast and one collision domain is created

PW = 100×Amount100+R×T